The present invention relates to ladder joints for folding collapsible ladders, and relates more particularly to such a ladder joint which permits an operator to fold up or adjust the folding collapsible ladder conveniently without the assistance of another person.
U.S. Pat. No. 5,353,892 discloses a ladder joint for a folding collapsible latter which comprises a pivot, a first base plate and a second base plate respectively turned about the pivot, a spring-supported lever pivoted to the pivot, and a lock bolt inserted through an eccentric hole on the second base plate and controlled by the lever to engage into one of a series of eccentric holes on the first base plate. This known of ladder joint is functional, but still has drawbacks. One drawback of this structure is that it can only be adjusted among three different angles. Another drawback of this structure of is that the lever must be constantly depressed by hand so that the first and second base plates can be turned about the pivot relative to each other to adjust the angular position of the joint. Therefore, a single person cannot adjust the folding collapsible ladder without the assistance of another person.